x1,y1,x2,y2 = map(float,(input().split()))
print("{0}".format(((x1 - x2)**2 + (y1 - y2)**2)**(1/2))) x1,y1,x2,y2 = map(float,(input().split())) x1 map(float,(input().split())) map float input().split() ().split () input split y1 x2 y2 print("{0}".format(((x1 - x2)**2 + (y1 - y2)**2)**(1/2))) print "{0}".format(((x1 - x2)**2 + (y1 - y2)**2)**(1/2)) "{0}".format "{0}" format ((x1 - x2)**2 + (y1 - y2)**2)**(1/2) (x1 - x2)**2 + (y1 - y2)**2 (x1 - x2)**2 x1 - x2 x1 x2 2 (y1 - y2)**2 y1 - y2 y1 y2 2 1/2 1 2 x1,y1,x2,y2 = map(float,(input().split())) map(float,(input().split())) x1 y2 = map(float,(input().split())) map(float,(input().split())) y2 y1,x2,y2 = map(float,(input().split())) map(float,(input().split())) y1 x2,y2 = map(float,(input().split())) map(float,(input().split())) x2
x1,y1,x2,y2 = map(float,(input().split()))
print("{0}".format(((x1 - x2)**2 + (y1 - y2)**2)**(1/2)))